// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  'use strict';

  CodeMirror.defineMode('sparql', function(config) {
    var indentUnit = config.indentUnit;
    var curPunc;

    function wordRegexp(words) {
      return new RegExp('^(?:' + words.join('|') + ')$', 'i');
    }
    var ops = wordRegexp([
      'str',
      'lang',
      'langmatches',
      'datatype',
      'bound',
      'sameterm',
      'isiri',
      'isuri',
      'iri',
      'uri',
      'bnode',
      'count',
      'sum',
      'min',
      'max',
      'avg',
      'sample',
      'group_concat',
      'rand',
      'abs',
      'ceil',
      'floor',
      'round',
      'concat',
      'substr',
      'strlen',
      'replace',
      'ucase',
      'lcase',
      'encode_for_uri',
      'contains',
      'strstarts',
      'strends',
      'strbefore',
      'strafter',
      'year',
      'month',
      'day',
      'hours',
      'minutes',
      'seconds',
      'timezone',
      'tz',
      'now',
      'uuid',
      'struuid',
      'md5',
      'sha1',
      'sha256',
      'sha384',
      'sha512',
      'coalesce',
      'if',
      'strlang',
      'strdt',
      'isnumeric',
      'regex',
      'exists',
      'isblank',
      'isliteral',
      'a',
      'bind',
    ]);
    var keywords = wordRegexp([
      'base',
      'prefix',
      'select',
      'distinct',
      'reduced',
      'construct',
      'describe',
      'ask',
      'from',
      'named',
      'where',
      'order',
      'limit',
      'offset',
      'filter',
      'optional',
      'graph',
      'by',
      'asc',
      'desc',
      'as',
      'having',
      'undef',
      'values',
      'group',
      'minus',
      'in',
      'not',
      'service',
      'silent',
      'using',
      'insert',
      'delete',
      'union',
      'true',
      'false',
      'with',
      'data',
      'copy',
      'to',
      'move',
      'add',
      'create',
      'drop',
      'clear',
      'load',
    ]);
    var operatorChars = /[*+\-<>=&|\^\/!\?]/;

    function tokenBase(stream, state) {
      var ch = stream.next();
      curPunc = null;
      if (ch == '$' || ch == '?') {
        if (ch == '?' && stream.match(/\s/, false)) {
          return 'operator';
        }
        stream.match(/^[\w\d]*/);
        return 'variable-2';
      } else if (ch == '<' && !stream.match(/^[\s\u00a0=]/, false)) {
        stream.match(/^[^\s\u00a0>]*>?/);
        return 'atom';
      } else if (ch == '"' || ch == "'") {
        state.tokenize = tokenLiteral(ch);
        return state.tokenize(stream, state);
      } else if (/[{}\(\),\.;\[\]]/.test(ch)) {
        curPunc = ch;
        return 'bracket';
      } else if (ch == '#') {
        stream.skipToEnd();
        return 'comment';
      } else if (operatorChars.test(ch)) {
        stream.eatWhile(operatorChars);
        return 'operator';
      } else if (ch == ':') {
        stream.eatWhile(/[\w\d\._\-]/);
        return 'atom';
      } else if (ch == '@') {
        stream.eatWhile(/[a-z\d\-]/i);
        return 'meta';
      } else {
        stream.eatWhile(/[_\w\d]/);
        if (stream.eat(':')) {
          stream.eatWhile(/[\w\d_\-]/);
          return 'atom';
        }
        var word = stream.current();
        if (ops.test(word)) return 'builtin';
        else if (keywords.test(word)) return 'keyword';
        else return 'variable';
      }
    }

    function tokenLiteral(quote) {
      return function(stream, state) {
        var escaped = false,
          ch;
        while ((ch = stream.next()) != null) {
          if (ch == quote && !escaped) {
            state.tokenize = tokenBase;
            break;
          }
          escaped = !escaped && ch == '\\';
        }
        return 'string';
      };
    }

    function pushContext(state, type, col) {
      state.context = {
        prev: state.context,
        indent: state.indent,
        col: col,
        type: type,
      };
    }
    function popContext(state) {
      state.indent = state.context.indent;
      state.context = state.context.prev;
    }

    return {
      startState: function() {
        return { tokenize: tokenBase, context: null, indent: 0, col: 0 };
      },

      token: function(stream, state) {
        if (stream.sol()) {
          if (state.context && state.context.align == null)
            state.context.align = false;
          state.indent = stream.indentation();
        }
        if (stream.eatSpace()) return null;
        var style = state.tokenize(stream, state);

        if (
          style != 'comment' &&
          state.context &&
          state.context.align == null &&
          state.context.type != 'pattern'
        ) {
          state.context.align = true;
        }

        if (curPunc == '(') pushContext(state, ')', stream.column());
        else if (curPunc == '[') pushContext(state, ']', stream.column());
        else if (curPunc == '{') pushContext(state, '}', stream.column());
        else if (/[\]\}\)]/.test(curPunc)) {
          while (state.context && state.context.type == 'pattern')
            popContext(state);
          if (state.context && curPunc == state.context.type) {
            popContext(state);
            if (
              curPunc == '}' &&
              state.context &&
              state.context.type == 'pattern'
            )
              popContext(state);
          }
        } else if (
          curPunc == '.' &&
          state.context &&
          state.context.type == 'pattern'
        )
          popContext(state);
        else if (/atom|string|variable/.test(style) && state.context) {
          if (/[\}\]]/.test(state.context.type))
            pushContext(state, 'pattern', stream.column());
          else if (state.context.type == 'pattern' && !state.context.align) {
            state.context.align = true;
            state.context.col = stream.column();
          }
        }

        return style;
      },

      indent: function(state, textAfter) {
        var firstChar = textAfter && textAfter.charAt(0);
        var context = state.context;
        if (/[\]\}]/.test(firstChar))
          while (context && context.type == 'pattern') context = context.prev;

        var closing = context && firstChar == context.type;
        if (!context) return 0;
        else if (context.type == 'pattern') return context.col;
        else if (context.align) return context.col + (closing ? 0 : 1);
        else return context.indent + (closing ? 0 : indentUnit);
      },

      lineComment: '#',
    };
  });

  CodeMirror.defineMIME('application/sparql-query', 'sparql');
});
